The tire uniformity is one of the most important quality items, and improvement of this level is a significant development challenge. In the uniformity, there have been a wide variety of activities to investigate and address each of factors which worsen RFV in its causal relationship and the results have been maintained and controlled in order to improve this level, which has achieved improvement to some extent.
However, there are countless factors to worsen RFV and it is extremely difficult to take a measure against each of them and to maintain and control it, and it is getting hard to take a measure against individual factor and to further improve RFV using a method to maintain and control it. In the meantime, regardless of the factor, such a method is being examined for tires of a required size that information based on the waveform of RF measured online is fed back to a manufacturing process and a predetermined RFV variation factor is controlled online so as to improve RFV, but since there is no effective method for controlling RFV variation factor, it has hot been realized yet.
The present invention has been made in view of the above problem and it relates to a tire producing method in which information based on the waveform of RF measured online is fed back to a manufacturing process so as to control a predetermined RFV variation factor online, and its object is to provide an effective method to control the RFV variation factor and a tire molding machine which enables it so as to improve the level of RFV.